textproduct: Rapid City

KEY MESSAGES

- Cooler with chances for light snow through Saturday.

- 1 to 3 inches of snow over the Black Hills through Friday, with another couple of inches Friday night and Saturday.

- Breezy northwest winds Friday and Saturday, especially across the western South Dakota Plains.

DISCUSSION

(This Evening Through Wednesday) Issued at 148 PM MST Wed Jan 7 2026

Upper level analysis shows quasi-zonal flow aloft with split flow to the west. There is a low off the southern California coasts and a weak open trough in the pacific Northwest. At the surface, a cold front extends from southwestern Saskatchewan through eastern Montana into southern Idaho. At 21Z, temperatures were mainly in the 50s, with westerly winds.

As the upper flow begins to turn southwest tonight, the cold front over Montana will move quickly through the forecast area. Moisture is fairly limited, but a few showers are possible overnight along with increased cloud cover.

The open trough over the Pacific Northwest moves over the Rockies on Thursday as weak high pressure at the surface moves over the Dakotas. Southwest flow aloft will increase moisture, resulting in cloudy skies. Pops will increase during the day, with light precipitation/showers expected mainly over the Black Hills, but can't rule out a few showers on the plains.

Light precipitation will become more widespread across the forecast area Thursday night as the trough approaches and a weak cold front moves through. Cold air and gusty northwest winds behind the front will result in colder, but seasonal, temperatures for Friday. Upslope precipitation looks to continue over the northern Black Hills and Bear Lodge Mountains. Overall, snowfall amounts for northeastern Wyoming and the Black Hills look to be in the 1 to 3 inch range.

Main upper trough moves through Friday night, bringing more chances for snow and colder temperatures. Again, moisture is not overly abundant but forcing should be sufficient enough for a little bit of snow across the area. Snowfall amounts of 1 to 3 inches over the Black Hills and Bear Lodge are possible, with maybe a dusting elsewhere.

Western high pressure quickly develops Saturday night and Sunday, allowing temperatures to warm up above average again by Sunday.

AVIATION

(For the 00Z TAFS Through 00Z Thursday Evening) Issued At 423 PM MST Wed Jan 7 2026

A cold front will move through the area tonight bringing gusty northwesterly winds at times. Patchy light snow may occur behind the cold front, most likely over northeastern WY/Black Hills where isolated MVFR conditions could develop tonight. Better chances for snow develop after 08/18z. Otherwise, VFR conditions will prevail.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.